Show strong connection, no data, though...

Hello--
I have a problem in that my younger son's laptop (dell inspiron 1525, shipped with Vista, I "upgraded" to Xp sp3) shows an excellent wireless connection at his mom's house, but Google's front page barely loads. To complicate matters, his older brother's laptop (older Dell, Xp sp3) connects and transfers data with no problem. This would seem to rule out router issues. However, the problem computer connects wirelessly at MY house with no issues. My wireless is through my fios box. Both houses are running wep 64 bit. I have run virus and spyware scans, with no apparent issues. Please help...

"My wireless is through my fios box." This seem to be the only difference, what is the connection at his mothers house.
The only other idea is to do a windows repair, there may be a small fault from the initial installation.

To Repair Windows XP from your XP CD…..

1. Re-start PC with XP CD in drive (Have your serial number handy)
2. As your PC starts press “F12” for boot menu (Or what your PC may ask for)
3. Scroll to and select “boot from CD.”
4. At prompt “Press any key to boot from CD” Press “Any key”
5. In the Windows XP Setup window, Press “Enter” to set up windows XP, (Don’t worry, this is a repair only, not a fresh install.)
6. At next window, Press “F8” to accept license agreement
7. Wait until windows displays your current version of XP and asks “To repair the selected windows XP installation press R”
8. Press “R”
9. Enter serial number when prompted.
10. Wait for files to be copied (PC will indicate 39 mins, it will take a lot less.)
11. When asked to adjust Regional language options, click “Next” as it is still set.
12. PC will re-boot.
13. If you have AVG Free, copy serial number to a file as you will lose it on repair. After repair a window will pop up asking how you want to treat AVG, Click repair and when prompted enter serial number.
14. Check to see if problem still exists.